On Fri, 28 Feb 2014 07:36:32 -0500, Stormin Mormon
wrote:

On 2/27/2014 10:31 PM, micky wrote:
Yes, years ago and I'm still doing it. Well, I close the vent using the
lever that does that. I assume I'm saving money to the extent parts of
the house (that I don't use much) are colder than they would be. The
basement is definitely colder. In fact maybe I should open the vent
since now I have the computer down here and I'm here so much. I have
the spare bedroom door closed, a towell under its door, and the vent
closed, and it's definitely cooler in that room. Never gets cold I
think. Maybe heat goes through the door and the walls. Etc .

I've been told, here probably, that if I close too many, that will cause
combustion problems with my oil furnace, but now that I think about it,
that makes little or no sense. The air I'm preventing from circulating
is not the combustion air. That comes in somewhere (????) and goes out
the chimney.

The air I'm stopping is the air on the other side of the heat exchanger.
If that circulates less, I suppose it gets hotter while it's in the
furnace, but not so hot it's going to heat the fire chamber** and change
the combustion characteristics of the oil fire.

**That is, fail to cool the fire chamber as much. It will do that a
little, but it's already so hot in the middle of an atomized oil fire, I
don't think it will change anything.

Another misunderstanding.

The evidence of it working,

I said at the top that I assume I'm saving money.

is that rooms are colder,

For just this reason.

and heat bill goes down. Hard to compare
heat bill, but got to figure it's doing some
thing.

I too can't really tell if the cost has gone down because I didnt' keep
records before I closed the vents, and I'd have to keep track of degree
days from one year to the next and gallons of oil delivered and it's too
much effort.

When I say at the end I don't think it will change anything, I mean I
don't think it will change the character of an oil (or gas) fire to
either make the air in the house dirtier or make more carbon monoxide,
or something else I wouldn't like. DD3 says the same thing, iiuc.
But someone here in the last 15 years once said it would, and iirc no
one posted a disagreement.